Hey, folks! Pittsburgher here, got an old Hitachi 60SDX88B, wonderful set, very happy with it.
Lately, a problem has developed. The picture - all three colours - will shrink horizontally, appearing to "pulse" wide and short, and then once it passes a certain threshold the picture disappears and will not return until the set is powered off, left for a minute or so, then powered on again. After power-off, sometimes a rhythmic "tick" can be heard from the inside of the set, starting at about one tick per second and gradually slowing down. Sometimes the set will not turn back on again, and will give me that rhythmic tick instead - when this happens, the speakers are initialized (I can hear the thump as power is sent to them), but the picture tubes don't get any power (I can't hear the static "futz" that happens when the tube is energized).
The tick doesn't have the same quality as a relay clicking over, but I can't see any obvious arcing inside the set.
Looking inside, there are several green LED's which pulse simultaneously in time with the tick when it's present. No bulging caps, burn marks, or other obvious signs of trouble.
The service manual says to short the gate and cathode of a 400v thyristor, observe whether or not I get a picture, and go from there. My questions:
1. Should I short those pins while the set is running, or put some heavy wire in place and then turn on the set?
2. Does anyone with more experience have a better idea? I know these service manuals only talk in very broad generalities.
3. Am I bonkers for even trying this? The most dangerous thing I've done to this set so far has been replacing the convergence STK's.
4. Is anyone from Pittsburgh willing to have a go at this for some cash money?